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Related papers: Revisiting the relation between nonthermal line wi…

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Aims. Estimates of coronal wave energy remain uncertain as a large fraction of the energy is likely hidden in the non-thermal line widths of emission lines. In order to estimate these wave energies, many previous studies have considered the…

Solar and Stellar Astrophysics · Physics 2021-12-08 Lianne Fyfe , Thomas Howson , Ineke De Moortel , Vaibhav Pant , Tom Van Doorsselaere

It is now well established that the Alfv\'enic waves are ubiquitous in the solar corona. However, the Alfv\'enic wave energy estimated from the Doppler velocity measurements in the corona was found to be four orders of magnitude less than…

Solar and Stellar Astrophysics · Physics 2019-09-04 Vaibhav Pant , Norbert Magyar , Tom Van Doorsselaere , Richard J. Morton

Observed spectral profiles of emission lines from the corona are found to have widths exceeding the thermal line width. To investigate the physical mechanism, we run a 3D MHD model of a single, straightened loop in which we partially…

Solar and Stellar Astrophysics · Physics 2024-04-02 C. A. Breu , H. Peter , S. K. Solanki , R. Cameron , I. De Moortel

MHD waves permeate the solar atmosphere and constitute potential coronal heating agents. Yet, the waves detected so far may be but a small subset of the true existing wave power. Detection is limited by instrumental constraints, but also by…

Solar and Stellar Astrophysics · Physics 2017-02-03 Patrick Antolin , Ineke De Moortel , Tom Van Doorsselaere , Takaaki Yokoyama

Transverse magnetohydrodynamic (MHD) waves have been shown to be ubiquitous in the solar atmosphere and can in principle carry sufficient energy to generate and maintain the Sun's million-degree outer atmosphere or corona. However, direct…

Solar and Stellar Astrophysics · Physics 2015-08-19 Takenori J. Okamoto , Patrick Antolin , Bart De Pontieu , Han Uitenbroek , Tom Van Doorsselaere , Takaaki Yokoyama

Spectral line widths are often observed to be larger than can be accounted for by thermal and instrumental broadening alone. This excess broadening is a key observational constraint for both nanoflare and wave dissipation models of coronal…

Solar and Stellar Astrophysics · Physics 2016-03-23 David H. Brooks , Harry P. Warren

The heating of the solar chromosphere and corona to the observed high temperatures, imply the presence of ongoing heating that balances the strong radiative and thermal conduction losses expected in the solar atmosphere. It has been…

We consider MHD waves as a heating source of cool cores of galaxy clusters. In particular, we focus on transverse waves (Alfven waves), because they can propagate a longer distance than longitudinal waves (sound waves). Using MHD…

Astrophysics · Physics 2009-11-13 Yutaka Fujita , Takeru K. Suzuki , Takahiro Kudoh , Takaaki Yokoyama

The mechanism behind coronal heating still elude direct observation and modelling of viable theoretical processes and the subsequent effect on coronal structures is one of the key tools available to assess possible heating mechanisms.…

Solar and Stellar Astrophysics · Physics 2020-11-11 P. Pagano , I. De Moortel , R. J. Morton

Whilst there are observational indications that transverse MHD waves carry enough energy to maintain the thermal structure of the solar corona, it is not clear whether such energy can be efficiently and effectively converted into heating.…

Solar and Stellar Astrophysics · Physics 2019-02-27 Paolo Pagano , Ineke De Moortel

The discovery of ubiquitous low-frequency (3-5mHz) Alfvenic waves in the solar chromosphere (with Hinode/SOT), and corona (with CoMP and the Solar Dynamics Observatory, SDO) has provided some insight into the non-thermal energy content of…

Solar and Stellar Astrophysics · Physics 2015-06-12 Scott W. McIntosh , Bart De Pontieu

In the near future, Parker Solar Probe will put theories about the dynamics and nature of the transition between the solar corona and the solar wind to stringent tests. The most popular mechanism aimed to explain the dynamics of the nascent…

Solar and Stellar Astrophysics · Physics 2021-03-17 N. Magyar , V. M. Nakariakov

A simplified non-linear numerical model for the development of incompressible magnetohydrodynamics (MHD) in the presence of a strong magnetic field B0 and stratification, nicknamed Shell-Atm, is presented. In planes orthogonal to the mean…

Astrophysics · Physics 2011-02-11 E. Buchlin , M. Velli

(abridged) We investigate how the properties of the corona and solar wind in the open coronal holes depend on the properties of the magnetic fields and their footpoint motions at the surface, by perfoming 1D MHD simulations from the…

Astrophysics · Physics 2015-06-24 Takeru K. Suzuki , Shu-ichiro Inutsuka

We consider compressive viscosity and thermal conductivity to study the propagation and dissipation of long period slow longitudinal MHD waves in polar coronal holes. We discuss their likely role in the line profile narrowing, and in the…

Astrophysics · Physics 2008-11-26 B. N. Dwivedi , A. K. Srivastava

We present a measurement of the energy carried and dissipated by Alfv\'en waves in a polar coronal hole. Alfv\'en waves have been proposed as the energy source that heats the corona and drives the solar wind. Previous work has shown that…

Solar and Stellar Astrophysics · Physics 2015-06-15 Michael Hahn , Daniel W. Savin

It is well established that the transverse MHD waves are ubiquitous in the solar corona. One of the possible mechanisms for heating both open (e.g. coronal holes) and closed (e.g. coronal loops) magnetic field regions of the solar corona is…

Solar and Stellar Astrophysics · Physics 2022-01-05 Samrat Sen , Vaibhav Pant

We present a new global model of the solar corona, including the low corona, the transition region and the top of chromosphere. The realistic 3D magnetic field is simulated using the data from the photospheric magnetic field measurements.…

Recent observations of reflected propagating and standing slow-mode waves in hot flaring coronal loops have spurred our investigation into their underlying excitation and damping mechanisms. To understand these processes, we conduct 2.5D…

Solar and Stellar Astrophysics · Physics 2024-04-01 Tongjiang Wang , Leon Ofman , Stephen J. Bradshaw

There is intense interest in determining the precise contribution of Alfv\'enic waves propagating along solar structures to the problems of coronal heating and solar wind acceleration. Since the launch of SDO/AIA, it has been possible to…

Solar and Stellar Astrophysics · Physics 2015-06-22 J. O. Thurgood , R. J Morton , J. A. McLaughlin
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